Attachment plug



Dec. 7 1926.

S. M CLATCHIE ATTACHMENT PLUG Filed July 14', 1920 Patented Dec. 7,1926.

v arre srar or I LINOIS.

Application filed July 14,

My invention relates to attachment plugs.

One of .the objects of my invention is to provide a swivel attachmentplug which will be durable-and eiiicient in use, easy to wire, simple inconstruction and cheap to manufacture. I

Further objects will appear fromthe detail description to followand'from the ap pended claims.

In the drawings in which an embodiment of my invention is shown,

Fig. 1 is an axial section ofan attachment Plug? Flg. 2 1s a sectlon onthe line 22 of Fig. 1; a

Fig. 3 is a section on the line 8-3 of Fig; 1; i

, Fig. 4 1s a section substantially line 1-4 of Fig. 1; and

on the Fig. 5 is a side elevation of the inside base and associatedparts. a The attachment plug shown in the drawing comprises in a generalway, a center' contact 10, a threaded shell contact 11, wiring terminals12 and 18 respectively, for'the contacts 10 and 11 and a two-partinsulating base 14 for affording the necessary support and insulationfor the contacts 10 and 11, and the wiring-terminals 12 and 13. A handleor thumbpiece 15 is secured to the threaded shell contact 11, forscrewing the threaded shell contact into a socket, this thumbpiece beingof insulating materialand serving'to house the :wiring terminals 12 and13; The threaded shell contact 11 is swiveled with respect to the wiringterminals 12 and 13 so that the plug can be screwed into the socketwithout twisting the cord secured to the wiring terminals.

Referring now more in detail to the construction, the two-partinsulating base 1 1 comprises an outside base part or cap 16, whichsupports the center contact 10 and an inside base part 17, whichsupportsthe wiring terminals 12 and 13. An annular sliding contact member 18 issecured'to the cap 16. This sliding contact member 18 may be formed ofsheet metal, having a portion 19 flanged over the outside base portion16 and secured in place thereon; The lower surface of the contact memberrests on the inwardly-extending annular flange 20 of the threaded shellcontact 11.

wiring terminal 12. v V l jThis U-shaped conducting'strap 22 has a...binding plate portion 23 for cooperation imam;

rarer a 1 STANLEY McCLATCi-IIE, or CAMBR GE. MASSACHUSEITS,ASSIG1\TOR r0BENJAMIN ELECTRIC manurao'roame COMPANY, or oHicAeo ILLm'oIs, aooaroanaroiv armeonivrnnr mile] 1929. Serial No. 396,216. f

The base 14 is held in placein the threaded shell contact after it isassembled by means of a contact finger or tongue 21,'struck up from thesliding contact finger 18, this contact finger21 extendingunder theinwardly.

extending flange 20, when the parts of the baseare in assembledposition. The base parts-16 and 17 may be assembled with re spectto eachother and with respect to the threaded shell contact 11 by inserting'theinside base part ,17 (carrying thewiring tersv m'in'als 12 and 13) intothethreadedshell contact, and then putting. the cap or outside base partin place by a lateral movement to V engage the contact finger ortongue"21' un-t derneathtlie flange of the threaded shellcontact, theparts being secured by threading the center contact screw 10 into theU-shaped conducting strap. 22,

with the head of'the binding screw 24;,which binding screw has its innerend threaded into the U-shaped conducting strapg22,

When the base parts 16 and 17 are not'connected together by means of thecenter contact screw 10 the U-shaped conducting strap 22 is held inplace-by means ofthe binding screw 2a whichprevents the U shapedstrap'from slipping off side-wise. I

To electrically connect the jsliding contact member 18 with thebinding'screw 25 ofthe. wiring terminal 13, a U-shapedconducting strap26 is provided, the upper arm 27 of which is engaged by the slidingcontact 19,

and the lower arm 28 of which 1 forms a binding plate portion lforcooperation with the binding screw 25. The upper end of forming part ofthe j this conducting strap 27 is prevented from slipping ofisidewisefrom the inside base portion 17 by means of a downwardlyextendinglug 29, and the lower end of the conducting strap is preventedfrom slipping oifsidewise by means of the inner end of the shank. of thebinding screw 25 which extends into a recess 30 of the inside baseportion 17.

In assembling this conducting strap por- I tion 26 on the base portion17 ,the upper end 7 of the strap is firsthooked over the correspondingpart of the base portion 17,- and the lower end is then swung inwardly,and

piece 15 to the threaded shell contact 11, the

upper end or we handle 15 is provided with an externally-threadedannular flange por tion 34, which is threaded into the lower end of thethreaded shell 11. In order to prevent the thumbpiece 15 from becomingunscrewed from the threaded shell contact after it has been screwed in,a tongue is struck in from the threaded shell contact and extends into aproperly located recess 36 in the inside base. portion 15. I g

In wiring the plug, it is not necessary to disconnect the handle 15 fromthe threaded shell contact 11. The plug may be wired as follows: Thecenter contact 10 is unscrewed from the conducting strip 22, the outsidebase portion 16 is slipped sidewise to disengagethe finger 21' from theflange of the threaded shell contact 11, and the inside base part 17 isslipped out of the threaded shell contact 11. The threaded shell contact11,

r with the handle 15 is then slipped over the ends of the wires 38 andthe ends of these wires 33 are looped over the strain reliet'lugs 31 and32 and secured underneath the heads of the binding screws 24 and 25. Theinside base part 17 carrying the wiring terminals 12 and 13 is thendrawn back into the threaded shell contact 11, this base part 17 beingcentered with respect to the tnreaded shell contact by means or" thethumbpiece 15 at its lower end, and by means of the annular flange 20 ofthe threaded shell contact at its upper end. The outside base part orcap 16 is thenput in position by sidewise movement to engage thefinger21 underneath the flange 20 and the center contact screw 10 isthen screwed into place, thensecuring the two base parts together, andelectrically connecting the center contact with the binding screw 24.

It is obvious thatif desired the handle 15 could be made easilydetachablefrom the applicants copending application Serial No. 3

393,973, filed July 3, 1920.

Having thus described myinvention, what I claim as new and desire tosecure by Letters Patent is:

1. An attachment plug comprising a contact for engagement with areceptacle contact, a binding screw, an insulating base, and aconducting member mounted on said insu: lating base and electricallyconnecting said binding screw and contact, said plug being provided withmeans whereby one end of said conducting member is tulcrumed on saidinsulating base, and whereby said binding screw serves to secure theother end-of said conducting member to hold it against swingingmovement.

2. An attachment plug comprising a contact for engagement with areceptacle contact, a binding screw, an insulating base, and

a conducting member'mounted on said in-;

sulating base and electrically connecting said bind ng screw andcontact, said plug being provided with means whereby one end of saidconducting member is :tulcrumed on said insulatingbase, said insulatingbase having a recess therein, and said binding screw being threaded intosaid conducting memher, and having its shank extending into said recessto prevent I said conducting member from swinging about its fulcrum.

In witness whereof, I have hereunto subscribed my name.

